The answer will depend on what aspect the 21 units refer to!
Quantity K is metric for 1000. For units, it can also refer to Kelvin temperature. It can also refer to Kinetic energy.
one unit is
Square unit
A unit ratio.
Well, in the metric system, the base unit for distance is the meter. If that is the unit to which you refer, then there are 1000 milimeters in one "unit", or meter.
eurasia
A cylinder can refer to a grain silo or a tiny pellet. A reasonable unit for one will not be reasonable for the other!
What sort of objects does this refer to?
The unit for energy is the joule. That's also the unit for work and for heat - both of which refer to energy transfers.
The acronym EBU is most often used to refer to the European Broadcasting Union. It may also be used to refer to an equivalent billing unit or an electronics bay unit.
18th infantry
15 units of wheat are given up to get one more unit of steel.
In Greek, "gram" (γραμμή) means "line" or "stroke." It can also refer to a unit of measurement equal to one thousandth of a kilogram.
If you refer to the unit, the international unit for energy is the joule; the symbol is "J".
The unit ratio for quarters (one-fourth of something) is 4:1Since there are 4 quarters to 1 of whatever you want to refer to, that means for a unit of 1 million, there are 4 million quarters.
In slang, "unit" can refer to a person who is strong, tough, or reliable. It is often used to describe someone who is capable or impressive in some way.